To estimate the incidence, chronicity, and remission of symptoms of insomnia and to examine factors associated with the incidence and chronicity of insomnia among adolescents.
Data were collected using diagnostic interviews and questionnaires from 4175 youths aged 11 to 17 years at baseline, and 3134 of these youths followed-up a year later. Subjects were sampled from large managed care populations in a metropolitan area of over 4.7 million. Insomnia was assessed by youth-reported DSM-IV symptom criteria.
One year incidence was 13.9% for 1 or more symptoms, 5.5% for 1 or more symptoms plus daytime fatigue or sleepiness, and 5.3% for insomnia caseness. Rates of chronicity were 45.8% for 1 or more symptoms, 34.7% with daytime fatigue or sleepiness, and 22.8% for insomnia caseness. There were no effects of age, sex, or family income in predicting incidence or chronicity of insomnia. There was a weak association of both somatic and psychological dysfunction with risk of future sleep outcomes, with stronger prediction for psychological dysfunction.
These results document further the public health burden of insomnia among adolescents. Prevalence of insomnia is comparable to that of other major psychiatric disorders such as mood, anxiety, disruptive, and substance use disorders. Incidence over one year also is high. Insomnia represents a chronic condition, further enhancing burden.